Lecture 14 Restriction Mapping

Restriction mapping involves cleaving DNA clones at specific sites with enzymes to produce a set of fragments. These fragments have characteristic lengths which together constitute a multiset (a set allowing repeated elements) called the “fingerprint” of the clone. Clones that overlap with each other share common restriction fragments as long as the region of overlap contains at least two enzyme cleavage sites. The goal of restriction mapping is to compare the fingerprints among clones to infer a linear ordering of the enzyme cleavage sites along the target DNA. Since these sites occur more frequently than STS tags, restriction mapping produces a relatively fine scale physical map.